These forgefix general purpose pozidrive screws with countersunk heads are zinc plated for increased durability they are an extremely popular general purpose screw and suitable for use in and with many materials applicationideal for use in many ironmongery electrical and plumbing applications can be used with various screw cover caps zinc coatings prevent oxidation of the protected metal to create a longer lasting finish it does this by forming a barrier and by acting as a sacrificial anode if t